ACUTE RHEUMATIC FEVER

 Multisystem disorder typicaly follows an episode f strep.pharyngitis(2-3 weeks) and usually presents with fever,anorexia,lethargy and joint pains.  Autoimmune consequence of infection (pharyngeal infection not the skin infection) with Group A beta haemolytic streptococcal infection  Generalized inflammatory response affecting brains, joints, skin, subcutaneous tissues & the heart

ACUTE RHEUMATIC FEVER Supporting evidences:  About 66% of the patients with an acute episode of rheumatic fever have a history of an upper respiratory tract infection 2-3 weeks before  The peak age (6-15 yrs) & seasonal incidence of acute rheumatic fever closely parallel those of GABHS infections

ACUTE RHEUMATIC FEVER Predisposing factors:  Family history of rheumatic fever  Low socioeconomic status (poverty, poor hygiene, medical deprivation)  Age: 5-15 years

 Very rare in developed counteries while still endemic in developing counteries.  Histologically,fibrinoid degeneration in collagen CT  Aschoff nodules are pathognomonic,only in the heart(multinucleatd gaint cells surronded by macrophage and T lymphocytes)

CLINICAL MANIFESTATIONS  No pathognomonic clinical or laboratory finding for acute rheumatic fever  Duckett Jones in 1944 proposed guidelines to aid in diagnosis & to limit overdiagnosis  Jones criteria for the diagnosis of acute rheumatic fever 2 major criteria or 1 major & 2 minor criteria pluse supporting evidence (microbiologic or serologic) of recent GABHS infection

DIAGNOSIS(JONES CRITERIA ) MAJOR MANIFESTATIONS MINOR MANIFESTATIONS SUPPORTING EVIDENCE OF ANTECEDENT GROUP A STREPTOCOCCAL INFECTION ****** Carditis Clinical features: Arthralgia Fever Previous rheumatic fever -Elevated or increasing streptococcal antibody titer(Antistreptolysin O) -Positive throat culture or rapid streptococcal antigen test or streptococcal sore throat or recent scarlet fever) Polyarthritis Laboratory features: Elevated acute phase reactants: ESR, C- reactive protein Prolonged PR interval Leucocytosis Erythema marginatum Subcutaneous nodules Chorea

MAJOR MANIFESTATIONS

Arthritis  Most common (75%)  Usually an early feature  Involves larger joints: the knees, ankles, wrists & elbows  Rheumatic joints: hot, red, swollen & exquisitely tender (friction of bedclothes is uncomfortable  The joint involvement is characteristically migratory in nature  A dramatic response to even small doses of salicylates is another characteristic feature of the arthritis

Carditis  Carditis & chronic rheumatic heart disease: most serious manifestations of acute rheumatic feve  Occurs in 50% of patients  pancarditis with active inflammation of myocardium, pericardium & endocardium  May manifest as SOB,palpitations or chest pain.  Other features, tachycardia out of proportion to fever, cardiac enlargment & cardiac murmurs(soft systolic murmur,soft mid diastolic murmur Carey coombs), aortic regurgitation in 50%, other valves rarely involved.

Carditis  Pericarditis may cause chest pain,pericardial rub.  ECG changes are common ST,T wave,conduction defects.  Echocardiographic findings: pericardial effusion, decreased ventricular contractility & aortic &/or mitral regurgitation  The major consequence of acute rheumatic carditis is chronic, progressive valvular disease

Chorea Sydenham chorea: one third of patients with acute rheumatic fever  More in females  A long latency period (1-6 mo) between streptococcal pharyngitis & the onset of chorea  Begins with emotional lability & personality changes (poor school performance).  Followed in 1-4 weeks by characteristic spontaneous, purposeless involentery chorea movement of the hands,feet or face (lasts 4-8 months) followed by motor weakness  Recovery within few monthes,1/4 will develop chronic rheumatic valve disease.

Erythema Marginatum  A rare (<5% of patients with acute rheumatic fever) but characteristic rash of acute rheumatic fever  It consists of erythematous, serpiginous, macular lesions with pale centers that are not pruritic  It occurs primarily on the trunk & extremities, not on the face & it can be accentuated by warming the skin

Subcutaneous Nodules  A rare (5-7% of patients with acute rheumatic fever) finding  Consist of firm,painless nodules approximately 1 cm in diameter along the extensor surfaces of tendons near bony prominences  A correlation between the presence of these nodules & significant rheumatic heart disease

MINOR MANIFESTATIONS

Clinical:  1. Arthralgia (in the absence of polyarthritis as a major criterion)  2. Fever (typically temperature ≥102°F & occurring early in the course of illness)  Previous rheumatic fever Laboratory minor manifestations:  1.Elevated acute-phase reactants (C-reactive protein, erythrocyte sedimentation rate, polymorphonuclear leukocytosis)  2. Prolonged PR interval on electrocardiogram (1st degree heart block)

ESSENTIAL CRITERIA An absolute requirement for the diagnosis of acute rheumatic fever is supporting evidence of a recent GABHS infection

DIFFERENTIAL DIAGNOSIS ARTHRITIS Rheumatoid arthritis Reactive arthritis (Shigella, Salmonella, Yersinia) Serum sickness Sickle cell disease Malignancy Systemic lupus erythematosus Lyme disease (Borrelia burgdorferi) Gonococcal infection (N.gnorrhoeae)

TREATMENT  Bed rest :reduce joint pains and cardiac workload, till symptoms and markers of inflammation settled  Antibiotic Therapy:  10 days of orally administered penicillin or erythromycin or a single intramuscular injection of benzathine penicillin to eradicate GABHS from the upper respiratory tract  Afterwards, the patient should be started on long-term antibiotic prophylaxis

TREATMENT  Anti-inflammatory Therapy:  Aspirin relieve symptoms of artheritis and prompt response helps to confirm the diagnosis. starting dose 100 mg/kg/day in 6 divided doses PO for 6 days, followed by 75 mg/kg/day in 6 divided doses PO for6 wk or till ESR has fallen then gradually tailed off.

TREATMENT  Corticosteroids are Indicated in cases of carditis or sever artheritis  Prednisone 1 mg/kg/day in 4 divided doses for 2-6 wk or till the ESR IS NORMAL then tailed off gradually.

TREATMENT  Supportive therapies for patients with moderate to severe carditis include digoxin, fluid & salt restriction, diuretics & oxygen  The cardiac toxicity of digoxin is enhanced with myocarditis

PREVENTION PRIMARY-10 days course of penicillin therapy; about 30% of patients with acute rheumatic fever do not recall a preceding episode of pharyngitis SECONDARY-Secondary prevention is directed at preventing acute GABHS pharyngitis in patients at substantial risk of recurrent acute rheumatic fever

SECONDARY PREVENTION  For how long? CATEGORYDURATION Rheumatic fever without carditisAt least for 5 yr or until age 21 year, whichever is longer Rheumatic fever with carditis but without residual heart disease (no valvular disease) At least for 10 yr or well into adulthood, whichever is longer Rheumatic fever with carditis & residual heart disease (persistent valvular disease) At least 10 yr since last episode & at least until age 40 yr; sometime lifelong

SECONDARY PREVENTION  What method of prophylaxis should be used? DRUGDOSEROUTE Penicillin G benzathine 600,000 U for children, ≤27 kg 1.2 million U for children >27 kg, every 4 wk Intramuscular OR Penicillin V250 mg, twice a dayOral OR Sulfadiazine or sulfisoxazole 0.5 g, once a day for patients ≤60 lb; 1.0 g, once a day for patients >60 lb Oral